Question

SURFACE AREAS AND
EXERCISE15.1
213
6. The cost of sheet for it, if a sheet measuring Imº costs Rs 20.
4.
*7.50 per
m.
The floor of a rectangular hall has a perimeter 250 m. If the cost of painting the four
walls at the rate of 10 per m’is* 15000, find the height of the hall
(Hint: Area of the four walls =Lateral surface area.)
The paint in a certain container is sufficient to paint an area equal to 9.375 m². How
many bricks of dimensions 22.5 cm 10 cm x 7.5 cm can be painted out of this
container?
5. A cubical box has each edge 10 cm and another cuboidal box is 12.5 cm long, 10 cm
wide and 8 cm high.
(1) Which box has the greater lateral surface area and by how much?
c) Which box has the smaller total surface area and by how much?
1. A plastic box 1.5 m long, 1.25 m wide and 65 cm deep is to be made. It is opened at the
top. Ignoring the thickness of the plastic sheet, determine:
2. The length, breadth and height of a room are 5 m, 4 m and 3 m respectively. Find the
cost of white washing the walls of the room and the ceiling at the rate of
(1) The area of the sheet required for making the box.​

Answer 1

Step-by-step explanation:

1) rs 20 × 545/100 = rs 109

2) 250 h × 10 m²=15000m²

2500h=15000

h=150/25 =6